Triangle calculator
Triangle has two solutions: a=38.5; b=34.5; c=5.14552145419 and a=38.5; b=34.5; c=56.75217637256.
#1 Obtuse scalene triangle.
Sides: a = 38.5 b = 34.5 c = 5.14552145419Area: T = 58.91444489058
Perimeter: p = 78.14552145419
Semiperimeter: s = 39.0732607271
Angle ∠ A = α = 138.4110608231° = 138°24'38″ = 2.41657208333 rad
Angle ∠ B = β = 36.5° = 36°30' = 0.6377045177 rad
Angle ∠ C = γ = 5.0899391769° = 5°5'22″ = 0.08988266433 rad
Height: ha = 3.06604908523
Height: hb = 3.41553303714
Height: hc = 22.90106772899
Median: ma = 15.42107365693
Median: mb = 21.37328593394
Median: mc = 36.46441151247
Inradius: r = 1.50878197495
Circumradius: R = 299.0002339927
Vertex coordinates: A[5.14552145419; 0] B[0; 0] C[30.94884891338; 22.90106772899]
Centroid: CG[12.03112345586; 7.63435590966]
Coordinates of the circumscribed circle: U[2.5732607271; 28.88659007729]
Coordinates of the inscribed circle: I[4.5732607271; 1.50878197495]
Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 41.5899391769° = 41°35'22″ = 2.41657208333 rad
∠ B' = β' = 143.5° = 143°30' = 0.6377045177 rad
∠ C' = γ' = 174.9110608231° = 174°54'38″ = 0.08988266433 rad
How did we calculate this triangle?
1. Input data entered: side a, b and angle β.

2. From angle β, side a and b we calculate c - by using the law of cosines and quadratic equation:


Now we know the lengths of all three sides of the triangle and the triangle is uniquely determined. Next we calculate another its characteristics - same procedure as calculation of the triangle from the known three sides SSS.

3. The triangle circumference is the sum of the lengths of its three sides

4. Semiperimeter of the triangle

5. The triangle area using Heron's formula

6. Calculate the heights of the triangle from its area.

7. Calculation of the inner angles of the triangle using a Law of Cosines

8. Inradius

9. Circumradius

#2 Obtuse scalene triangle.
Sides: a = 38.5 b = 34.5 c = 56.75217637256Area: T = 649.8276913357
Perimeter: p = 129.7521763726
Semiperimeter: s = 64.87658818628
Angle ∠ A = α = 41.5899391769° = 41°35'22″ = 0.72658718203 rad
Angle ∠ B = β = 36.5° = 36°30' = 0.6377045177 rad
Angle ∠ C = γ = 101.9110608231° = 101°54'38″ = 1.77986756563 rad
Height: ha = 33.75772422523
Height: hb = 37.6711125412
Height: hc = 22.90106772899
Median: ma = 42.83662445014
Median: mb = 45.32204572239
Median: mc = 23.04547245266
Inradius: r = 10.01664636641
Circumradius: R = 299.0002339927
Vertex coordinates: A[56.75217637256; 0] B[0; 0] C[30.94884891338; 22.90106772899]
Centroid: CG[29.23334176198; 7.63435590966]
Coordinates of the circumscribed circle: U[28.37658818628; -5.9855223483]
Coordinates of the inscribed circle: I[30.37658818628; 10.01664636641]
Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 138.4110608231° = 138°24'38″ = 0.72658718203 rad
∠ B' = β' = 143.5° = 143°30' = 0.6377045177 rad
∠ C' = γ' = 78.0899391769° = 78°5'22″ = 1.77986756563 rad
Calculate another triangle
How did we calculate this triangle?
1. Input data entered: side a, b and angle β.

2. From angle β, side a and b we calculate c - by using the law of cosines and quadratic equation:


Now we know the lengths of all three sides of the triangle and the triangle is uniquely determined. Next we calculate another its characteristics - same procedure as calculation of the triangle from the known three sides SSS.

3. The triangle circumference is the sum of the lengths of its three sides

4. Semiperimeter of the triangle

5. The triangle area using Heron's formula

6. Calculate the heights of the triangle from its area.

7. Calculation of the inner angles of the triangle using a Law of Cosines

8. Inradius

9. Circumradius
